Came here to post the exact same thing. Recently got a 2018 Enclave Avenir and thought there was something wrong with it. It only once shutoff when stopped and it started to shutoff then immediately turned on again. I then read the owner's manual more closely and it lists a whole lot of reasons why it may not turn off. I keep the A/C on 65 and it almost never turns off. As soon as I turn off the A/C of up the temp, it turns off at almost every stop.
